Mystery in San Francisco

Green Apple is a series of richly illustrated graded readers especially designed for elementary school students. The series is based on internationally recognized standards of lexical and structural control from beginner to elementary, offering original stories as well as adapted classics in a variety of genres.Beginner: Written completely in the present tense with very simple vocabulary and grammar for students who are just starting English Grammar covered: Present Simple/Continuous - be/have got - can, cannot, must imperatives - lets (do) simple time clauses - verbs and prepositions Basic: Written in the present and past simple tenses, using simple vocabulary and grammar. Grammar covered: Past Simple regular/irregular - will future - could Elementary: Although the story is still written in the present and past simple tenses, there are longer sentences, more joining words and a richer vocabulary. Grammar Covered: Past Continuous - present/past passive form - verb + gerund/infinitive if clauses (type 0) - comparatives/superlatives regular/irregular simple phrasal verbs - would, should, need Features of the Green Apple series: introduction on the author wide variety of stimulating activities to develop the four skills including internet projects extensive footnotes with picture illustrations wherever possible informative dossier sections containing useful background information about